(1) Field of the Invention
The present invention generally relates to a mail center management system.
(2) Description of the Prior Art
Recently, a new network has been proposed in which a mail center, which provides various mail services by means of various media, such as speech, facsimile and images, is provided in the network. For example, such a main center is provided in a local area network. Generally, the mail center is designed, taking into account a future increasing demand of mail services. Hence, it is desired that the main center can be easily expanded without greatly changing the system configuration.
In the past, two communication devices, such as facsimile machines, transferred information between them. However, recently, there has been a demand to send identical information to a plurality of destination devices. For example, it is required to simultaneously send identical information to a plurality of persons and customers via a network. For this requirement, a mail center as described above is connected to the network. Generally, a single main center is connected to the network. As the number of users increases and/or the number of mails increases, line circuits connected to the network are increased. In addition to an increase in the number of line circuits, or instead thereof, a storage device, such as a disk device, is added to working storage devices. In some cases, some working storage devices may be replaced with new ones.
If some working storage devices are replaced with new ones, information stored therein must be transferred to the new storage devices. During this data transfer process (a few days to a few weeks), the mail services are not available. Further, there is a possibility that some information may be lost or damaged during the data transfer process.